'Hoop Dreams' director Steve James tackles the prevalence of head injuries in sports in 'Head Games,' with testimony by athletes like Christopher Nowinski.

The documentary "Head Games" looks at the problem of concussions… (Variance Films )

"Head Games" isn't fooling around. It's a complex, determined look at one of the most pernicious problems facing organized sports on all levels, but because its director is Steve James, this is more than your standard problem documentary.

James is not only the director of "Hoop Dreams," the consensus pick as the best sports doc ever made, he is also, as last year's "The Interrupters" demonstrated, a filmmaker with an unusually deft touch. There's more nuance in "Head Games," more space for a wider perspective, than we usually see in films that tell us in no uncertain terms that the sky is falling.

This particular piece of sky is the pervasiveness of concussions in sports and what that potentially means for the athletes who get them. For many years, the just-do-it culture of sport meant that everyone involved — fans, coaches, management, even the players themselves — either ignored or minimized the dangers in that quite prevalent kind of head injury.

"Head Games" initial task is to show us how that consensus began to change, initially through the efforts of Christopher Nowinski, who parlayed being an All-Ivy defensive tackle from Harvard into a career as a despised villain in professional wrestling's "Monday Night Raw."

When a serious concussion ended his career and led to a meeting with Boston University School of Medicine's concussion guru Dr. Robert Cantu, Nowinski ended up writing a book called "Head Games: Football's Concussion Crisis," which came to the attention of New York Times sportswriter Alan Schwarz.

Schwarz, a strong screen presence with an ironic sense of humor, starts the film off by noting "It's been known for a long time that banging your head over and over and over again can be a bad thing."

Starting in 2007, Schwarz wrote a series of articles that backed up that assertion with specifics. It turned out that an autopsy had revealed that Andre Waters, a former NFL player who committed suicide, had the same brain disease — chronic traumatic encephalopathy or CTE — that was thought only to afflict boxers and that likely led to his depression and his death.

More links followed, as did the leaking of a University of Michigan study that showed that retired NFL players ages 30 through 49 were 19 times more likely than the average American of their age group to be diagnosed with Alzheimer's or related ailments. Statistics like that, and the resulting uproar, definitely got the league's attention and ended the denials of risk.

This may sound like a straightforward science-on-the-march journey, but in fact this progression was a complicated one, and James does a fine job of leading us through the nuances of how it all went down.

One complication is that, as with smoking and lung cancer, every person who gets a concussion is not going to develop crippling brain damage, so the question becomes how far do we go with preventive measures. Though some sports figures say the danger is overstated, Nowinski feels strongly that "if I had a 6-year-old playing football, I would be freaked out and rightly so. You're playing Russian roulette with their future."

Though football gets all the headlines because of the popularity of the NFL, concussions are a problem in any endeavor that features collisions, and "Head Games" takes us through several of them with the help of a different example in each sport.

Talking about hockey is Keith Primeau, an NHL All-Star with the Philadelphia Flyers who felt so dreadful after a fourth concussion that he was actually relieved when the club doctors told him his career was over. Though the NHL is now intent on eliminating needless injuries, "Head Games" points out that the prevalent feeling among fans that fighting is part of hockey's tradition makes that a difficult assignment.

Though you wouldn't necessarily expect it, women's sports, especially soccer, lead to a surprising amount of concussions. Especially troubled was Cindy Parlow Cone, a mainstay of the U.S. Women's National Team. She estimates that half of her goals in her career were headers, and she's been so plagued by concussion aftereffects that she uses a GPS even on the most familiar streets.

One of the things that sets "Head Games" apart is its understanding of how difficult it would be to take concussions' risks as seriously as they should be taken. For one thing, an effective protocol might end professional sports as we know them. For another, even parents who know better are shown to have difficulty keeping their children away from these activities because they love them so much. There are, Primeau says, "no guarantees in life," and changing rules turns out to be easier than changing the culture.